土壤水分和养分对筇竹竹鞭解剖特征及其适应可塑性的影响

Anatomical Characteristics and Adaptive Plasticity of Qiongzhuea tumidinoda Rhizome under Different Soil Moisture and Nutrients Conditions

【目的】探究不同土壤水分和养分条件下的筇竹(Qiongzhuea twnidinoda)竹鞭解剖结构特征,旨在比较不同生境中筇竹竹竿的适应对策。【方法】采用冗余分析与蒙特卡洛检验方法,测定分析了3个土层深度0~40 cm、0~80 cm和0~120 cm筇竹林竹鞭解剖结构特征及其与土壤养分、水分的关系。【结果】(1)随着土壤水分和养分含量的增加,筇竹竹鞭的纤维组织、输导组织比量以及维管束密度呈现显著减小的趋势(P<0.05);但基本组织比量、维管束长度、宽度和长宽比则呈现显著增加的趋势(P<0.05)。(2)薄土层生境筇竹竹鞭组织比量、维管束和纤维大小的变异系数及可塑性指数均为最大。(3)土壤水分和养分对筇竹竹鞭解剖结构有着显著影响(P<0.05),单一土壤因子对筇竹竹鞭解剖结构影响的重要性大小排序为土壤含水量>速效K>有机质>全K>有效P>全P>水解N>全N>pH值。【结论】土壤水分、K及有机质含量对竹鞭形态建成有重要影响,筇竹通过调控竹鞭解剖结构及其塑性来适应土壤因子的限制。生产上,可通过调控土壤水分含量、增施K素和有机肥来促进竹鞭生长发育。

【Objective】This paper aims to explore the anatomical characteristics of natural Qiongzhuea tumidinoda rhizome under different soil water and nutrient conditions,and to compare the adaptive strategies of Q.tumidinoda rhizome in different habitats.【Method】The relationship among the anatomical structure characteristics of Q.tumidinoda rhizome,soil nutrient and water in three soil depths(0-40 cm,0-80 cm and 0-120 cm)was analyzed by using redundancy analysis and Monte Carlo test.【Result】(1)With the increase of soil water and nutrient content,the proportion of fibrous tissue,conducting tissue and vascular bundle density decreased significantly(P<0.05);However,the basic tissue ratio,vascular bundle length,width and aspect ratio of Q.tumidinoda rhizome showed an obvious increasing trend(P<0.05).(2)Among the three soil thickness habitats,the variation coefficient and plasticity index of Q.tumidinoda rhizome including tissue ratio,vascular bundle and fiber size in thin soil layer habitat were the largest.(3)Soil moisture and nutrient factors had significant effects on the anatomical structure of bamboo rhizome(P<0.05).The importance of a single soil factor on the anatomical structure of Q.tumidinoda rhizome was in following order:soil water content>available K>organic matter>total K>available P>total P>hydrolyzed N>total N>pH.The difference of soil moisture and nutrient content was the fundamental reason affecting the anatomical structure plasticity of Q.tumidinoda.【Conclusion】Soil moisture,K and organic matter content had important effects on the formation of bamboo rhizome.Q.tumidinoda can adapt to the restriction of soil factors by regulating the anatomical structure and plasticity of bamboo rhizome.Therefore,in production,the growth and development of bamboo rhizome can be promoted by regulating soil moisture content,addition of K and organic fertilizer.